1. Technical Field of the Invention
The present invention relates to an antigen activator and a method for activating an antigen immuno-cell or immuno-tissue during chemical staining, and particularly to an improved method and a regent thereof for expose (activate, unmask, or retrieve) an antigenicity, when cells or tissues on a slide glass are stained immuno-tissue-chemically.
2. Description of the Prior Art
Conventionally three antigen activators such as citrate buffer solution, urea added tris salt buffer solution, and ethylenediaminetetraacetate (EDTA) are mainly used for activating the antigen during immuno-staining by heat and pressurization treatment.
Concretely, the following antigen activation methods are known;
(1) The activation method by using a citrate buffer solution of pH 6.0 and concentration 0.01 mol. and by pressurization, heating, or humidification by using a microwave oven, autoclave, electric pot, constant-temperature bath, or scalder.
(2) The activation method by using a citrate buffer solution of pH 7.0 and concentration 0.01 mol. containing 5% urea by pressurization and and heating by using an autoclave.
(3) The activation method by using pH 9.5 and concentration 0.1 mol. tris-HCl buffer solution containing 5% urea by pressurization, heating, or humidification by using a microwave oven, autoclave, electric pot, constant-temperature bath, or scalder.
(4) The activation method by using an EDTA solution of pH 8.0 and concentration 0.01 mol. by pressurization, heating, or humidification by using a microwave oven, autoclave, electric pot, constant-temperature bath, or scalder.
Those are main techniques currently employed.
Further, reference documents are listed below;
1) Shi S. R., Key, M. E., “Kalra, K. L; Antigen retrieval in formalin-fixed, paraffin-embedded tissues: an enhancement method for immunohistochemical staining based on microwave oven heating of tissue sections. J. Histochem. 39: 741-748,1991
2) Shi S. R., Cote R. J., Young L., Imam S. A. Taylor C. R.: Use of pH 9.5 Tris-HCl buffer containing 5% urea for antigen retrieval immunohistochemistry, Biotechnic & Histochemistry 71(4): 190-6, 1996 July.
3) Cattoretti G., Becker M. H. G, Key G., et al.: Monoclonal antibodies produced against recombinant parts of the Ki-67 molecule (MIB-1 to -3) stain proliferating cells in formalin fixed, paraffin-embedded, microwave processed tissues. Histochem J. 234: 611, 1992 (Abstr.)
4) Shin R. W., Iwaki T., Kitamono T., et al.: Hydrated autoclave pretreatment enhances tan immunoreactivity in formalin-fixed normal and Alzheimer's disease brain tissues. Lab. Invest. 64: 693-702, 1991
5) HAMAKAWA Shinji : An investigation on antigen activation by heat treatment during enzyme-antibody staining using anti-CD4 monoclonal antibody (Byohri to Rinshoh (Pathology and Clinical Pathology)) 1999, 17(11): 1201-1205)
6) HAMAKAWA Shinji : An investigation on an antigen activator in place of EDTA solution (Byohri Gijutu (Pathological Techniques)) 1999, 60: 10-14
Currently, the antigen activators are selected, depending upon object antigens. However, the current technique has disadvantages that the working procedures are complex, the activation of the antigen is imperfect, and the reproducibility of activation is poor.